xdict = {
    'a': 'av',
    'b': 100,
    200: 20000,
}

xkeys_to_check = ['a', 'b', 'c', 100, 200, 300]

for k in xkeys_to_check:
    flag = False
    if k in xdict:
        flag = True
    print(f'{k}: {flag}')
